Convection is a mode of heat transfer for which types of objects

If you put a helium-filled balloon in the refrigerator, what will happen?

Aweather balloon has a volume of 52.5 liters at a temperature of 252 k. the balloon is released and rises to an altitude where the temperature is 295 k. how does this temperature change affect the gas particle motion?

City b is south of city a, and the 200 mile trip by car takes 4 hours. the cities are 120 miles apart in a straight line. what is the velocity of a trip from city a to city b?